As the journey continues, there's beauty and danger in equal measure. Charley and Ewan travel through the extraordinary Bolivian desert, but the sandy roads make all more difficult. The duo ride their electric bikes through the exotic and breathtaking countryside and all the way making a challenging ascent. The riders stay in a hotel made entirely out of salt before heading to La Paz. 'Bolivia' also shows some quality work done by UNICEF when it comes to educating and working with the children. McGregor and Boorman spend time with the kids before resuming their journey and ending with a ferry ride over lake Titicaca.

For Charley Boorman and Ewan McGregor, their journey in the smooth Ecuadorian roads would most definitely have come as a relief after some rough terrain riding. Next up, they stop by one of the factories that make the famed Panama hats. One of the local producers explains that making them by hand takes roughly up to a month. At the other end, the crew on the Rivians make a dash for Central America where they have to ferry their trucks across as the Darién Gap blocks their path. On their way, they make a quick pitstop at one of the cacao factories to know more about cocoa production, one of the economic drivers of the country.

Ewan and Charley swap their e-Harley Davidsons for plane first and follow it up with a journey by ship to Panama. McGregor's bike needs some repairs and will be fixed by the time they reach Costa Rica. The ship they travel in with the bikes looks like a beaten-down vessel that raises genuine concerns about making the journey in one piece. The boat crew looks sharp and proactive while trying to make the show crew's journey as comfortable and safe as possible. The episode also introduces Nuqui, one of the wettest regions in the world where the ship quickly makes a pitstop to fuel up on essential supplies.

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